Apparatus for centrifugally forming canopies, or the like, of v-type cross sections



June 6, 1950 2,510,304

R. 8. AMES APPARATUS FOR CENTRIFUGALLY FORMING CANOPIES, OR THE LIKE, 0F V-TYPE CROSS-SECTIONS Filed April 1, 1949 INVENTOR.

. 4 Robert 8. lmes ATTORNEY Patented June 6, 1950 OFFICE APPARATUS FOR CENTRIFUGALLY FORM- ING CANOPIES, OR THE LIKE, OF V-TYPE CROSS SECTIONS Robert S. Ames, Akron, Ohio, assignor to Goodye r Aircrat C r o a k o i a o n ta ion of Delawar 8 Qlaimshis inv ntion rela es o a pa a us for centrit I ugally forming of therm plastic sheet ma erial, 019185, and, the like, for aircraft and in par.- eu e o an appa a us ada d t or a pie having V=shaped cross-section at least within a por on f eir eng In. the Patent No. 2,448,492 of Robert Mayne, a d Patent N 2, 8.2 of H, eterson, apparatus for centriiusal to nins. of can es having s stan all semi -circ l or oe 'eb eal cr ss-sec io s ar c ibed and lus r a f which th s n ention s a m d atio For air la s, ha ing Wind h d o v-sheeet QIQSSvSGQtiQIl, the, front portio of a canopy Q0112- n ct d he w h, in. rd ro f rm a sm oth nd st eaml n d continuat n t r us e,v ior at least a certain length, a similar crossrsectional ape w i h. m y fair ea werdly t a iff e hap To acc mp sh. h effec utoma i a by centrifu al o ming. a additiona feat cording to the invention. t e u ed in 60111158: ion w th either one of h above m n ned patented apparatus, has been develoned.

It s. t e en ral object of h n e ti n to P vide an apparatus for centrifugally forming of m p as shee mater a a a op or h like, having V-shaped cross-sections within at least a portion of its length and fairing this portion into the remaining portion thereof having substantially round or parabolical crosssections.

Another object of the invention is to provide in an apparatus for cen-trifugally forming of thermoplastic sheet material a canopy, or the lik having v shap d, c o s-secti s, h ta able jig determining the edge contours of the opy wi h mea s for ap ng b cen if al fo ce, at l ast within a porti n of t a opy length, the otherwise round or parabolical crosssections of the canopy into vrshaped crosse ece tiens fairing n o the r main g por ion t ereof- The resaid ob ct o the n enti n an other objects which will become apparent as the d sc p i roc eds, e achiev d by v ly mounting near the top in the center of the V-sh p fr porti n i t rota le ji w h mines he contour cf th e e po tion of he ca cer, a l n i ud na er of d s ed n ubstant a ly sha d to th contours o th finished canopy and which, the jig is being rotates, is c nt focally iorced out rdl a i h sheet aterial o be form d nto a canopy for having it assume varying V-shaped crosse section subst t ally t e -leriet o the he and For a better understandin of the invention reference should be had by the accompanying drawing, wherein Fig. 1 shows diagrammatically a longitudinal side view of a canopy.

Fig. 2 shows various cross-sectional views taken on lines a, b, c, d and e of Fig. l ota canopy formed with an apparatus according to the invention,

Fig. 3 shows, for comparison with Fig. 2, sirnie lar views taken on lines a, b and c of a canopy formed with an apparatus prior to the invention.

Fig. 4 shows a side view, partly in crqss-sec: tion, of one embodiment of the invention, and

Fig. 5 shows a cross-sectional view of the form? ing jig taken on line VV of Fig. 4.

Although the invention when, applied either to a female forming jig as in Patent No. 2,448,274, or to a male forming jig as in Patent No. 2,448,:

. 274, there is no principal difference in its con:

struction and, therefore, the invention is illuse trated only in connection with the former type jig, in both the centrifugal bar or arm is atach to the l por ion of he l Referring e spe fi al y to t e aw ng. th F g r 1, 2. n 3 sho a an y o he fo med by the apparatus illustrated and of which Fig. 2 shows several cross-sectional views of a cangpy m de h t e apparatu ac ordi to the in: ventioruand for comparison, similar views of a canopy having conventional cross-sectional contours.

The numeral l indicates a supporting irarne upon which is rotatably mounted i healing 2 a shaft 3 i n pu leys 4 rom a mo or, no Shown- T sha 3. bo e o fastened thereto a pair of split collars 5, one having extending therefrom in opposite direction u s B and l, nd the her on 6 nd B tween and. to the lugs 1, is pivqtally attached a k 9 d be w e and t t e lug e fix end niece l F om the ink 9 and he nd Piece H1 is suspended by brackets II on the female nor-.- tion 1 0f the forming jig into which is draped in hot condition the thermoplastic canopy ma:- terial M formed into an article A and secured therein around the edges by the male jig portion 3, sua ly ga n a o l er t, by any su t: ab e c m n mean no own- Th rr-ensemen is in nc le e om as the const e ion shown in Patent No. 2, 482%, o er w he difierence that at th r a x he he rames l5 and It of the female and male jig portions, re ec i e are not curved but. Pointed that to fai into the re s sect on rearwerdlr thereon the shape a th s end 91- he can p will to that of a. V-shaped Wind shield of an airplane to which it is to be attached. In order to continue the V-shape within a desired length by centrifugal forming and to fair it into the remaining portion of the canopy, which in crosssection has a rounded top, a bar or arm I? curved to the final shape of the longitudinal center contour of the canopy and of proper weight is pivotally mounted with one end at 58 to the center of the male end frame l6 and outward movement of the other end is restricted by a cord l9 attached to some point of frame it, or by any other means. Counterweights 2G adjustable on threaded extensions 2! radially to the shaft 3, which are inserted between and fastened to the lugs 6, serve to balance the weight of the jig, together with that of the work material.

In operating the apparatus, that is, by rotating the jig having the hot work material inserted therein, the bar II, as shown in dotted lines will be thrown by centrifugal force outwardly against the inside of the work material and form it therealong into V-shaped cross-section fairing into a curved shape produced merely by centrifugal force without use of any mechanical shaping means.

It will be recognized that the objects of the invention to produce a canopy, or the like, having V-shaped cross-section, at least for a portion of the canopy length, have been achieved. Moreover, it should be understood an apparatus according to the invention also would be applicable for obtaining a canopy of other than V-shaped by changing the centrifugal weight or bar accordingly.

While certain representative embodiments and details have been shown for the purpose of illustrating the invention, it will be apparent to those skilled in the art that various changes and modifications may be made therein without departing from the spirit or scope of the invention.

What I claim is:

1. Apparatus for centrifugally forming a transparent thermoplastic sheet into a streamlined canopy or the like, said apparatus being of the type including a jig for supporting the sheet adjacent its edges only and having substantially the entire center unsupported, means for rotating the jig about an axis to impart the desired shape to the unsupported portion of the sheet, said jig being characterized by a substantially V- shaped support portion adjacent the front of the canopy to be formed and by a spaced substantially U-shaped support portion on the jig adjacent the rear of the canopy to be formed, and a bar carried in association with the J'ig and movable by centrifugal force into engagement with the sheet adjacent the V-shaped support portion on the jig, said bar being positioned to impart a substantially V-shape in transverse section to the front portion of the canopy which blends into the U-shape of the canopy towards the rear.

2. Apparatus for centrifugally forming a transparent thermoplastic sheet into a streamlined canopy or the like, said apparatus being of the type including a jig for supporting the sheet adjacent its edges only and having substantially the entire center unsupported, means for rotating the jig about an axis to impart the desired shape to the unsupported portion of the sheet, said jig being characterized by a substantially V-shaped support portion adjacent the front of the canopy to be formed and by a spaced substantially U-shaped support portion on the 4 jig adjacent the rear of the canopy to be formed, and a bar-like means carried in association with the jig and movable by centrifugal force into engagement with the sheet adjacent the V-shaped support portion on the jig.

3. Apparatus for centrifugally forming a transparent thermoplastic sheet into a streamlined canopy or the like, said apparatus being of the type including a jig for supporting the sheet adjacent its edges only and having substantially the entire center unsupported, means for rotating the jig about an axis to impart the desired shape to the unsupported portion of the sheet, said jig being characterized by a bar carried in association with the jig and movable substantially laterally by centrifugal force into the sheet to form a portion thereof to approximate V- shape in sections taken substantially perpendicular to the bar and spaced along the bar.

4. In an apparatus for centrifugally forming a thermoplastic sheet into a, streamlined canopy, or the like, a jig rotatable about a longitudinal axis and being radially spaced therefrom for holding said sheet only along its edges and thereby determining the edge contours of the canopy having substantially V-shaped cross-section at the front and substantially U-shaped cross section at the rear, means for rotating said shaft, and bar means inside of and fulcrumed at one end near the top of the jig front portion, said bar means being shaped substantially to the longitudinal center contour of the front portion of the canopy to be centrifugally forced against the inside of the sheet to be formed transversely into V-shaped cross-sections fairing rearwardly thereof into the U-shaped portion of the canopy while the jig is being rotated.

5. In an apparatus for centrifugally forming a thermoplastic sheet into a streamlined canopy having bottom, front and rear edges, or the like, a rotatably mounted shaft, a jig radially spaced from and supported in fixed relation by said shaft for supporting said sheet around its edges and determining only the contours of the edge portions of the canopy and which when rotated forms the cross-sectional contours of the canopy, and bar means longitudinal of and in the center of said jig being swingably attached to the front thereof and which during jig rotation is forced centrifugally against the sheet to modify for a desired length the cross-sectional U-shape of the canopy into a substantially V-shaped cross-section, both portions fairing into each other.

6. In an apparatus for centrifugally forming a thermoplastic sheet into a streamlined canopy, having bottom, front and rear edges, or the like, a rotatably mounted shaft, a jig radially spaced from and supported in fixed relation by said shaft for supporting said sheet around its edges and de termining only the contours of the edge portions of the canopy and which when rotated forms the cross-sectional contours of the canopy and bar means longitudinal of and in the center of said J'ig and being swingably attached to the front thereof and which during jig rotation is forc centrifugally against the sheet to modify for a desired length the cross-sectional U-shape of the canopy into a cross-section substantially different from said U-cross-section, both portions fairing into each other.

'7. In an apparatus for centrifugally forming a thermoplastic sheet into a streamlined canopy, or the like, a jig rotatable about a longitudinal axis and being radially spaced therefrom for holding said sheet only along its edges and thereby determining the edge contours of the canopy, the crosssectional contours thereof being obtained by rotating the jig the front end ofwhlch is substantially V-shaped and the rear end substantially U-shaped in cross-section, and bar means swingably attached to the top front end and longitudinally of said jig for substantially modifying at least for a portion of its l'ength the cross-sectional shape of the canopy ordinarily obtained by the centrifugal action of said bar means.

8. In an apparatus for centrifugally forming a thermoplastic sheet into a streamlined canopy, or the like, a jig rotatable about a longitudinal axis and being radially spaced therefrom for holding said sheet only along its edges and there- No references cited. 

